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UNITED STATES DEPARTMENT OF AGRICULTURE 

BULLETIN No. 674 

Contribution from the Bureau of Animal Industry 
JOHN K. MOHLER, Chief 




SsJ9^^-ru 




Washington, D. C. 



PROFESSIONAL PAPER 



May 15, 1918 



HEMORRHAGIC SEPTICEMIA. 

By Henry J. Washburn, 
Senior Pathologist, Pathological Division. 



CONTENTS. 



Characteristics 1 

History 2 

Cause of the disease 3 

Symptoms 5 

Anatomical changes 6 



Page. 

Diagnosis 7 

Prevention 8 

Treatment 9 

Disinfection of premises 9 



CHARACTERISTICS. 

Hemorrhagic septicemia is an infectious disease, attended with a 
very high mortality, which attacks various species of animals, espe- 
cially cattle, sheep, and swine. Young animals are more susceptible 
to the disease than older ones, and those that are thin and poorly 
nourished are most liable to be affected. 

The disease is a septicemia, or poisoning of the blood, wherefore it 
often runs a short course and the affected animal quickly dies. In 
suddenness of attack and high mortality at the beginning of an out- 
break there is great resemblance to anthrax. 

In hogs the disease is known as swine plague. The acute form is 
usually fatal to hogs within a few hours from the appearance of the 
first symptoms. In chronic cases the affected hogs gradually become 
weaker and thinner and may linger for several weeks. 

Fowl cholera represents the avian form of hemorrhagic septicemia, 
and its attacks sometimes cause great losses. Pigeons and geese are 
susceptible to hemorrhagic septicemia and the introduction of the in- 
fection into flocks of birds of those kinds may lead to numerous 
fatalities. 

The disease usually results in death so quickly at the beginning of 
an outbreak that no forms of treatment have time to become effective. 
The apparently healthy animals should be separated from the dis- 
eased and placed in clean, uninfected quarters, where they should be 



46449°— Bull. 674—18 



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2 BULLETIN 674, U. S. DEPARTMENT OF AGRICULTURE. 

given the best, of feed and water. Bacterins, which may be purchased 
from the various manufacturers of biological products or from their 
agents throughout the country, have proved to be effective in many 
instances in checking the spread of an outbreak and in protecting the 
unaffected portion of the herd or flock. 

HISTORY. 

The disease occurred many years ago in this country in the form of 
swine plague. In 1885, through bacteriological studies that were car- 
ried on in the Bureau of Animal Industry, the Bacillus bipolaris 
suisepticus was identified as the cause of swine plague in the United 
States, and at the same time the disease was identified as the 
"Schweineseuche " of German writers. 

Hemorrhagic septicemia appeared among cattle in Kimble County, 
Tex., in 1896. It was noted that many deer in Kimble County were 
affected at the same time, and the fatalities were very numerous. 
Those that were carefully examined showed typical lesions of hemor- 
rhagic septicemia similar to those found in the affected cattle. It was 
not determined whether the deer or the cattle were the first to con- 
tract the disease. 

In 1898 cattle owners in Tennessee lost many of their young ani- 
mals from hemorrhagic septicemia. In this instance the infection 
appeared to be spread over a considerable area, and the disease 
seemed inclined to assume an unusually chronic character. 

Several outbreaks occurred among cattle in Minnesota in 1900. 
The cases were carefully studied by Brimhall and Wilson, and the 
cultural characteristics of the microorganism that was isolated from 
the affected cattle were definitely established. 

A year or two later some young cattle were affected while on a 
hilly pasture in central Virginia, where they had been feeding about 
one week when the disease appeared. Removing all the drove to a 
lowland pasture stopped the losses promptly. It was reported by the 
owner that it was necessary to abandon the mountain lot as a cattle 
pasture, as the disease recurred each spring if cattle were allowed 
to run over the infected areas. 

During the month of December, 1911, the Department of Agricul- 
ture was notified by the Department of the Interior that a fatal 
disease had appeared among the buffaloes in the Yellowstone Na- 
tional Park, young animals being most susceptible. In all, 22 buffa- 
Joes died between December 3 and December 15. Examination of 
specimens of affected organs at the Washington laboratory of the 
bureau revealed an infection with the specific microorganism of 
hemorrhagic septicemia, and pure cultures of those bacilli were 
obtained. In order to prevent a recurrence of the infection in the 



D. of D.- 
i>,AY 20 1918 



HEMORRHAGIC SEPTICEMIA. 3 

spring the entire herd of buffaloes was vaccinated with material 
prepared from the pure cultures obtained in Washington. Two 
vaccines of different strengths were prepared. The vaccine for the 
first inoculation was prepared by growing the organism 5 days at 
42.5° C. (108° F.), while the second was cultivated at the same tem- 
perature for only 2 days. 

This experiment was probably the first instance in which auto- 
genic vaccines were used in the United States for the prevention of 
hemorrhagic septicemia, and its success was so marked that similar 
steps were taken afterwards to check outbreaks among cattle, sheep, 
and goats, so that at the present time bacterins for the inoculation of 
infected herds and flocks are prepared by several firms which manu- 
facture biological products and may be purchased in all parts of the 
country. 

Anthrax appeared in several counties in Texas in 1913, and during 
the investigation of the outbreak two cases of hemorrhagic septi- 
cemia were discovered, one in a horse and the other in a sheep. The 
organisms recovered were identical with the bacilli, which recently 
have been recovered from outbreaks of hemorrhagic septicemia in 
cattle and goats. 

During the fall and winter of 1915-16 many cases were reported 
to the Bureau of Animal Industry in which young stock cattle that 
had been purchased in carload lots at some of the large stockyards 
had developed hemorrhagic septicemia within a few days after their 
arrival. At the same time two flocks of sheep and one of goats were 
found to be affected with the disease. Cultures of either the hemor- 
rhagic septicemia group of organisms or cultures closely related to 
the colon or paratyphoid B group were recovered from these cases. 

CAUSE OF THE DISEASE. 

The organism of hemorrhagic septicemia, the Bacillus bipolaris 
septicus, belongs to the group in which the bacilli of chicken cholera, 
swine plague, and rabbit septicemia are to be found. This group is. 
known also by the name Pasteurella. The individual organism is 
an ovoid, nonmotile, polar-staining bacterium with rounded ends, 
1/38000 of an inch wide by 1/20000 of an inch long, sometimes seen 
in pairs or chains, but usually appearing singly. It stains readily 
with the stains usually used in bacteriological work, and in many 
cases shows deep staining at each end, while the middle of the bacillus 
shows but little coloring. It forms no gas and quickly destroys itself 
while growing on solid culture media by the development of acids. 

The organism may be cultivated readily in bouillon and on agar 
and gelatin. The reaction of the medium should be slightly alkalin 
or neutral. It does not liquefy gelatin, coagulate milk, or produce 
indol. 



4 BULLETIN 674, U. S. DEPARTMENT OF AGRICULTURE. 

The bipolar staining property of the organism may be demon- 
strated readily in preparations made from the tissues or body flnids 
(kidneys, blood, etc.), cultures of the organism usually giving less 
pronounced results in this respect. 

Attempts have been made during an outbreak of hemorrhagic 
septicemia among cattle to transfer the disease from affected to 
healthy animals by means of rubbing saliva from diseased cattle into 
the mouths of healthy susceptible animals, and by injecting serum 
from the blood of a diseased yearling beneath the skin of susceptible 
young cattle, but without success. Many attempts to infect hogs by 
natural means from diseased cattle also have failed. In one in- 
stance, however, a colt that fed from the rack with a number of 
diseased sheep contracted the disease and died. 

The spread of the disease seems to depend nearly as much upon 
the condition and susceptibility of the animal as upon the contagious 
nature of the disease, as thin, poorly nourished young stock most 
frequently become infected and die of septicemia. 

In a number of outbreaks of a disease resembling hemorrhagic 
septicemia in all its manifestations and anatomical changes an or- 
ganism which differs in cultural characteristics from the true B. bi- 
polaris septicus has been recovered. This organism proves to be 
virulent for experimental animals (rabbits and guinea pigs), pro- 
ducing in them changes suggestive of hemorrhagic septicemia. In 
preparations from affected tissue or body fluids the organism stains 
bipolar, and usually occurs singly or occasionally in pairs. It differs 
from the true B. bipolaris septicus in that it appears slightly larger, 
possesses a sluggish motility, and produces gas in sugar media. In 
its cultural characteristics it corresponds in most instances to bac- 
teria of the colon group, although some of the characteristics pos- 
sessed by the paratyphoid B group have been noted. 

Bipolar ovoid bacilli which closely resemble the organism of 
hemorrhagic septicemia are widely distributed in nature. They 
•have been found in the soil, upon various plants, in stagnant water, 
and upon the moist nasal membranes of normal calves and hogs. 
In several instances these harmless organisms have been so increased 
in virulence by passing through animals that they finally proved to 
be fatal when injected into pigs, and in those instances the tissue 
changes, which were found at the autopsy of the pig, were similar 
to those found in swine that had died from swine plague. 

It is thought by some Avriters that after the organisms have be- 
come virulent enough to cause an outbreak among animals, they will 
later, after that infection has been overcome, return to their previous 
harmless stage. The increased virulence which is made evident by 
an attack of several animals of a single species appears to be effective 
only in animals of that particular species, and the disease does not 



HEMORRHAGIC SEPTICEMIA. 

spread to individuals of other species. For example, hogs and sheep 
that are pastured with a drove of cattle in which several deaths 
occur from hemorrhagic septicemia usually remain unaffected, al- 
though on another farm the sheep or the hogs alone may contract 
the disease and all the cattle escape. If any exceptions to this rule 
occur they are extremely rare. 

SYMPTOMS. 

In cattle the disease develops very rapidly, running a course of 
from 1 to 3 days. There is usually a steady elevation of body tem- 
perature until from 104° to 107° F. (40° to 41.67° C.) is reached. 
The animal refuses its feed. Swelling may appear beneath the skin 
of the head, throat, or dewlap. These enlargements are somewhat 
soft and pit on pressure. The tongue is often extensively swollen, 
and the animal drools and slobbers because of the irritation to its 
tongue and throat. There may be difficulty in breathing, depending 
on the degree of involvement of the air passages and of the lungs. 
Occasional coughing may occur. Muscular trembling may be evi- 
dent. There may be a blood-stained discharge from the nostrils, and 
strings of mucus may hang from the mouth. Examination of the 
nostrils often reveals the presence of many small hemorrhages just 
beneath their lining membranes. The eyelids become highly in- 
flamed and as a result tears flow down the cheeks. 

There is an intestinal form in which the changes are chiefly found 
in the abdominal cavity, or the intestinal form may develop after 
the disease has appeared in the lungs. The stomach, intestines, and 
kidneys and the lymph glands belonging to them become studded 
with hemorrhages of various sizes, and the intestines become in- 
tensely inflamed. The consequence of the developments is that diar- 
rhea sets in, accompanied with the passage of shreds of mucus and 
of bloody feces. The intestinal form is rare, as most cases show 
severe involvement of the lungs and the symptoms of croupous pneu- 
monia. The animals may stand with their forelegs wide apart in 
order to breathe more freely. They lose flesh very rapidly when 
affected with hemorrhagic septicemia, their abdomens become 
*' tucked up," and the eyes quickly become sunken. A staggering 
gait, caused by the extreme weakness of the patient, is sometimes 
noticed. 

A disease has been described under the name of septic pleuropneu- 
monia of calves, which is a form of hemorrhagic septicemia, and is 
caused by the Bacillus Mpolaris vitulisepticus. The symptoms shown 
by the affected calves are quite characteristic of hemorrhagic septi- 
cemia, and the post-mortem findings are also those found in that 
disease. 



6 BULLETIN 674, TJ. S. DEPARTMENT OE AGRICULTURE. 

In sheep, young animals which have just been weaned are found to 
he most susceptible, the disease manifesting itself in an acute form. 
There is marked depression, high temperature, labored respiration, 
loss of appetite, muscular trembling, and frequently colicky pains. 
A subacute and a chronic form of the disease are also recognized, the 
latter affecting principally older sheep. Aside from the febrile 
changes, weakness, etc., there is noted in the subacute form a dis- 
charge from the eyes and nose which at first is serous, later becoming 
purulent. There may be also pulmonary impairment (pneumonia), 
or there may be evidence of enteritis. Occasionally the symptoms 
subside only to return in a more chronic form, which manifests itself 
principally as a chronic affection of the lungs, with gradual emacia- 
tion of the animal. Sometimes the joints are involved, swelling of 
the knee joints being noted in some cases. 

In swine the disease sometimes manifests itself in a peracute form, 
the animal showing symptoms of a general septicemic condition. 
Ked spots may be noted on various parts of the body, especially 
around the ears and on the neck and rump. When affected with 
this form of the disease the animal usually dies within a few hours 
after the first manifestations of symptoms. In acute swine plague 
the disease usually occurs as a necrotic pleuropneumonia. There is 
labored respiration, dry, spasmodic cough, a slimy discharge from 
the nose, sometimes a purulent conjunctivitis, cyanotic membranes, 
constipation followed by diarrhea, the feces sometimes containing 
blood. The animal becomes greatly emaciated and usually dies in 
from 1 to 2 weeks. Sometimes the acute form changes into the 
chronic type, in which case the acute symptoms subside, and the 
cough and evidence of pulmonary involvement continue for a con- 
siderable time. Progressive emaciation occurs and a chronic inflam- 
mation of the joints may develop. The animals die in from 3 to 6 
weeks from complete exhaustion. Sometimes, however, the lung foci 
may become encapsulated, and the animals may even be fattened in 
spite of the condition of the lungs. 

ANATOMICAL CHANGES. 

Swellings will be found in the subcutaneous tissues. If these 
enlargements are examined they are found to consist of collections 
of jelly like material tinged with blood. Occasionally they are lim- 
ited to a single shoulder or flank, when they may be mistaken for 
blackleg. The lymph glands are enlarged and are injected with 
blood. The mucous membranes which line the respiratory tract 
are similarly affected. False membranes composed of fibrinous exu- 
date may develop in the throat. The spleen remains normal. Hem- 
orrhages are constant in the connective tissues around the kidneys 
and within the walls of the intestines. 



HEMORRHAGIC SEPTICEMIA. 7 

In the pectoral form the lungs are darkened in color with their 
fibrous tissues much thickened from the collection of bloody serum 
in their meshes. The diaphragm, heart sac, and heart walls show 
numerous bloody points and larger hemorrhages. 

In the intestinal form hemorrhages into the intestines will be 
present and sloughing of the lining of the intestinal wall will be 
observed, as a result of which the intestinal contents will be wrapped 
in a covering of bloody mucus. 

In acute forms the animals may die suddenly and the changes that 
are present in such cases will not be very marked. Microscopic ex- 
amination of the body fluids in these cases will demonstrate the pres- 
ence of numerous specific coccobacilli. 

DIAGNOSIS. 

Because of their acute course, high fever, and rapid termination 
in death, some difficulty may be experienced in distinguishing an- 
thrax, malignant edema, and blackleg from hemorrhagic septicemia. 
The differentiation of hog cholera from hemorrhagic septicemia of 
swine also presents many puzzling points. 

There may be edematous swelling of the throat or neck in either 
anthrax or hemorrhagic septicemia. An examination of the spleen 
of the affected animal will give a conclusive diagnosis, for the spleen 
of an animal dead from anthrax nearly always becomes acutely 
swollen and its pulp becomes softened. Small hemorrhages are usu- 
ally present in the kidney fat in cases of hemorrhagic septicemia. 
Bacteriological examination will demonstrate quickly the presence 
of the specific organisms of anthrax or of hemorrhagic septicemia, 
and a test should be applied in all cases in which doubt exists. The 
value of a definite diagnosis will be recognized when the lasting na- 
ture of an anthrax infection and the more transitory character of an 
outbreak of hemorrhagic septicemia are considered. 

Blackleg and malignant edema may be detected usually by the for- 
mation of gas within the swellings upon the body, and the bubbles- 
thus developed will produce a crackling sound if the fingers are 
pressed over the affected area. Further, in blackleg the marked 
change in the affected musculature and the characteristic " rancid- 
butter" odor noted in cases of blackleg facilitate a differential diag- 
nosis. 

Hemorrhagic septicemia of swine, commonly termed swine plague, 
usually appears in the form of necrotic pleuropneumonia. The 
symptoms shown by the affected animal readily point to an attack 
of pneumonia, but the presence of roundworms in the lungs may 
cause identical manifestations. The long course of the latter disease 
should be taken as an indication that the pig is not affected with 
swine plague. 



-8 BULLETIN 674, U. S. DEPARTMENT OF AGRICULTURE. 

It is very difficult to distinguish swine plague from hog cholera. 
The two diseases may occur in the same animal. Should the out- 
break seem to be but slightly contagious and not inclined to spread 
from the premises upon which it first appeared, it is probably not 
hog cholera, but, on the other hand, if it spreads rapidly throughout 
the neighborhood, it is undoubtedly due to hog-cholera infection. 
The presence of bipolar oval bacilli does not alone establish a diag- 
nosis of swine plague, since those organisms are frequently found as 
secondary invaders in true cases of hog cholera, and again they are 
often present in the noses and throats of healthy swine. 

PREVENTION. 

Animals and fowls may be protected experimentally from contract- 
ing hemorrhagic septicemia through the use of bacterins. Cattle, 
sheep, swine, rabbits, and fowls, if treated with heated cultures of 
hemorrhagic septicemia germs obtained from animals or birds of the 
same species as that to which they themselves belong, will almost in- 
variably become protected against injections of living cultures of 
the same germ, even though applied in comparatively large quanti- 
ties. Tests made by this bureau have shown that the use of cultures 
from animals of another species often affords similar complete im- 
munity. Sheep have been made immune from virulent cultures 
obtained from other sheep by the use of prepared cultures from cat- 
tle. Rabbits have been made resistant to hemorrhagic septicemia 
cultures, derived from a variety of different species of animals, by 
treatment with prepared cultures coming from animals of other 
species. They have been protected perfectly from inoculations with 
virulent cultures of the true Bacillus bovisepticus in doses four times 
as large as that required to produce fatal results in a rabbit receiv- 
ing no previous treatment. Fowls have been protected from injec- 
tions of deadly quantities of virulent fowl-cholera organisms by the 
use of prepared bouillon growths of the same germ, or by the use of 
strains of the fowl-cholera bacillus possessing but little virulence. 
However, when the colon or paratyphoid B group of organisms is 
found to be responsible for the deaths, the bacterins should include 
these germs. 

As a result of these investigations, and of others reported in medi- 
cal literature, it is customary, at the present time, in manufacturing 
bacterins for the protection of stock from attacks of hemorrhagic 
septicemia to use several cultures coming from a number of out- 
breaks of the disease for treating the same species of animals as that 
from which the cultures were obtained. For example, the bacterin 
for bovine hemorrhagic septicemia is being prepared from strains of 
the B. bovisepticus and not the B. suisepticus, or vice versa. 



HEMORRHAGIC SEPTICEMIA. 9 

Iii the October, 1916, issue of the American Sheep Breeder, Dr. 
W. H. Lytle, Oregon State Veterinarian, reports very satisfactory 
results from vaccination with an attenuated or weakened culture of 
the living organism. About 3,000 sheep were treated with the ma- 
terial. After 48 hours subsequent to the vaccination of the flocks 
only nine sheep were lost, although previous to inoculation several 
animals died each day. Bacterins made from the killed organisms of 
hemorrhagic septicemia have been used also with considerable success 
in Oregon bands of sheep. 

TREATMENT. 

In most cases treatment of a fully established case of hemorrhagic 
septicemia in an animal of any species is quite useless. All appar- 
ently well animals should be removed from those that are sick by 
placing them in separate, noninfected quarters. If new cases de- 
velop among them in a few days after their removal, the healthy 
ones remaining should be removed again to another locality. In 
that way the unaffected animals soon will be out of danger of further 
contamination, especially if their strength lias been supported by an 
abundance of good feed and water during the period of their separa- 
tion. 

DISINFECTION OF PREMISES. 

Premises usually become infected with hemorrhagic septicemia 
by stock cattle that have recently passed through some of the larger 
cattle markets. Owing to this method of infection the stables and 
yards may not be so completely contaminated as they would be if 
the disease had developed spontaneously. In any event, all stables, 
sheds, or yards that have contained infected animals should be dis- 
infected. The interior of the stables, especially the mangers and 
manure trenches, should be washed with a disinfectant, such as liquor 
cresolis compositus (U. S. P.) or carbolic acid, 6 ounces to a gallon 
of water in either case. The yards may be disinfected by the appli- 
cation of a solution made of 5 ounces of copper sulphate to a gallon 
of water. The best means of applying disinfecting solutions is 
afforded by the use of a spray pump such as is used in the spraying 
of orchard trees. All refuse and material from the stable and barn- 
yard should be removed to a place not accessible to cattle, sheep, or 
hogs. The manure should be spread on fields and plowed under. 
A plentiful supply of light and air should be provided for the con- 
taminated stables. Open fields or pasture lands are cleansed rapidly 
by the action of sunlight upon them. 



DEPARTMENT OF AGRICULTURE PUBLICATIONS RELATING TO 
DISEASES OF ANIMALS. 

AVAILABLE FOR FREE DISTRIBUTION. 

Milk Fever and Its Treatment. (Farmers' Bulletin 206.) 

The Tuberculin Test of Cattle for Tuberculosis. (Farmers' Bulletin 351.) 

Rabies or Hydrophobia. (Farmers' Bulletin 449.) 

Tuberculosis. (Farmers' Bulletin 473.) 

Methods of Disinfecting Stables. (Farmers' Bulletin 480.) 

Methods of Exterminating the Texas-Fever Tick. (Farmers' Bulletin 498.) 

Texas or Tick Fever. (Farmers' Bulletin 569.) 

Foot-and-Mouth Disease. (Farmers' Bulletin 666.) 

Sheep Scab. (Farmers' Bulletin 713.) 

Prevention of Losses of Stock From Poisonous Plants. (Farmers' Bulletin 720.) 

Tuberculosis of Hogs. (Farmers' Bulletin 781.) 

Anthrax or Charbon. (Farmers' Bulletin 784.) 

Contagious Abortion of Cattle. (Farmers' Bulletin 790.) 

The Sheep Tick and Its Eradication by Dipping. (Farmers' Bulletin 798.) 

Hog Cholera. (Farmers' Bulletin 834.) 

Screw-Worms and Other Maggots Affecting Animals. (Farmers' Bulletin 857.) 

Cattle Lice and How to Eradicate Them. (Farmers' Bulletin 909.) 

Important Poultry Diseases. (Farmers' Bulletin 957.) 

Directions for the Use of Blackleg Vaccine. (Bureau of Animal Industry 

Circular 23, fourth revision.) 
Blackleg; Its Nature, Cause, and Prevention. (Bureau of Animal Industry 

Circular 31, sixth revision.) 
Actinomycosis, or Lumpy Jaw. (Bureau of Animal Industry Circular 96.) 
The Contro 1 of Bovine Tuberculosis. (Bureau of Animal Industry Circular 

175.) 
Bighead in Sheep. (Leaflet A. I. 3.) 
Glanders and Farcy. (Leaflet A. I. 13.) 

FOR SALE BY THE SUPERINTENDENT OF DOCUMENTS, GOVERNMENT PRINTING 

OFFICE, WASHINGTON, D. C. 

Immunization Tests With Glanders Vaccine. (Department Bulletin 70.) Price, 

5 cents. 
The Granular Venereal Disease and Abortion in Cattle. (Department Bulletin 

106.) Price, 10 cents. 
The Effect of the Cattle Tick Upon the Milk Production of Dairy Cows. 

(Department Bulletin 147.) Price, 5 cents. 
Ophthalmic Mallein for the Diagnosis of Glanders. (Department Bulletin 166.) 

Price, 5 cents. 
The Dog as a Carrier of Parasites and Disease. (Department Bulletin 260.) 

Price, 5 cents. 
Experiments in Vaccination Against Anthrax. (Department Bulletin 340.) 

Price, 5 cents. 
10 



HEMORRHAGIC SEPTICEMIA. 11 

An Intradermal Test for Bacterium Pullorum Infection in Fowls. (Department 

Bulletin 517.) Price, 5 cents. 
The Control of Hog Cholera. (Department Bulletin 584.) Price, 5 cents. 
Tuberculosis of the Food-Producing Animals. (Bureau of Animal Industry 

Bulletin 38.) 1906. Price, 40 cents. 
Necrotic Stomatitis. (Bureau of Animal Industry Bulletin 67.) Price, 10 

cents. 
Osteoporosis or Bighead of the Horse. (Bureau of Animal Industry Circular 

121.) Price, 5 cents. 
Infectious Anemia or Swamp Fever of Horses. (Bureau of Animal Industry 

Circular 138.) Price, 5 cents. 
Lip-and-Leg Ulceration of Sheep. (Bureau of Animal Industry Circular 160.) 

Price, 5 cents. 
Diagnosis of Tuberculosis by Complement Fixation, With Special Reference to 

Bovine Tuberculosis. (In Journal of Agricultural Research, January 3, 

1917.) A-26. Price, 10 cents. 
Some Facts About Tuberculous Cattle. (Yearbook Separate 476.) Price, 5 

cents. 
Special Report on Diseases of Cattle. Price, $1. 
Special Report on Diseases of the Horse. Price, $1. 



WASHINGTON : GOVERNMENT PRINTING OFFICE : 1918 



,-iSSST 0F CONGRESS 



T ™»-.^™ 



